This invention relates to flow control valves for fluid conduit systems and more particularly to an improved automatically self-closing valve.
In many fluid conduit systems, it is essential to use valves that can be opened manually but are otherwise biased to the fully closed position, thereby preventing any valve from being inadvertantly left open after actuation. Heretofore, various attempts have been made to provide a suitable self-closing valve, but in general, such prior art devices were relatively complex and often unreliable and/or difficult to operate. Other devices, such as the flush valve shown in U.S. Pat. No. 3,360,234, failed to provide adequate intermediate flow control between the full open or full closed positions, a valve function that is vital in many fluid conduit systems. The present invention provides an automatically self-closing valve that solves the aforesaid problems.